The work aims to fabricate high-performance nanostructured non-transformable tetragonal 8YSZ feedstocks used for plasma spraying to meet the demand of high-end equipment by the nanopowder regranulation technique and then apply the feedstocks as the consumables of “aero-engine and gas turbine” and ceramic 3D printing. The nanostructured 8YSZ feedstocks used for plasma spraying were prepared by the nanopowder regranulation technology with nano-8YSZ powders as raw materials. The surface morphology, grain size and phase structure of nanostructured 8YSZ feedstocks were investigated by scanning electron microscopy (SEM), transmission electron microscopy (TEM) and X-ray diffraction (XRD). Meanwhile, the apparent density, tap density and flowability of nanostructured 8YSZ feedstocks were measured. The as-prepared nanostructured 8YSZ feedstocks exhibited spherical and smooth morphology. The feedstocks had smooth surface and dense internal microstructure. The feedstocks were in free-flowing state and the particle size met the requirements for plasma spraying. The grain size of nanostructured 8YSZ feedstocks did not grow obviously in the process of the nanopowder regranulation. The phase structure of feedstocks was non-equilibrium transformation tetragonal phase, i.e. T′ phase. The high performance nanostructured spherical T′ phase 8YSZ feedstocks with controllable particle size distribution and microstructure can be prepared by adjusting the process of nanopowder regranulation. The as-prepared high performance feedstocks are expected to be used in high-end equipment such as aero-engines and gas turbines, as well as ceramic 3D printing consumables.